Optic nerve glioma: the role of radiation therapy.

Sixteen patients with optic nerve gliomas were treated with radiation therapy between 1962 and 1975. Surgical extirpaton was not attempted. Fifteen patients had biopsies with histologic confirmation: one had a craniotomy without biopsy. With a follow-up of 1 to 14 years, mean 6.3 years, 12 of the 16 patients are alive without evidence of disease. Vision was preserved or improved in all surviving patients. No patients who received 5000 rad or greater had a recurrence of his tumor, whereas four of seven patients receiving doses less than 5000 rad had recurrences and eventually died. We currently recommend 5000-rad megavoltage photon irradiation, delivered with standard fractionation, for all patients with optic nerve gliomas.